Boiler



' J. BERENT BOILER Feb. 16, 1937.

Filed Sept. 20, 1935 4 Sheets-'Sheet l MNR SWK lwl I NNN AWORNEY J. BERENT Feb. 16, 1937.

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ATTORNEY J.BERENT BOILER Filed Sept. 20, 1955 Feb. 16, 1937.

4 Sheets-Sheet 3 AR Q im Ov MVENTOR ATTORNEY J. BERENT BOILER Feb. 16, 1937.

Filed Sept. 20, 1935 4 Sheets-Sheet 4 NvENToR M ATTORNEY Patented Feb. 16, 1937 UNITED STATES PATENT OFFICE BOILER John Berent, Lockport, N. Y.

Application September 20, 1935, Serial No. 41,436

16 Claims. (Cl. 122-122) This invention relates to a boiler and more par-4 ticularly to a low pressure boiler for heating water or generating steam for warming buildings, although the same is also useful in other installations.

The objects of this invention are to provide a boiler of this character, which is' constructed mainly of sheet steel or rolled boiler plate sections which are so organized that the same can be manufactured at low cost, which enables Water to be heated and steam generated quickly and economically, which has its interior readily accessible so that it can be easily cleaned and maintained in the most eicient condition, which can be utilized as an incinerator for burning rubbish, and which is capable of being made in sections so the same can be conveniently transported, also installed in places diicult of access and also permits of varying the number of sections in the boiler to suit the required capacity.

In the accompanying drawings:

Fig. l is a front elevation of a boiler embodying a satisfactory form of my invention.

Fig. 2 is a side elevation of the same.

Fig. 3 is a vertical longitudinal section, on an enlarged scale, taken on line 3 3, Fig. 1.

Fig. 4 is a vertical transverse section, on an enlarged scale, taken on line 4 5, Fig. 2.

Fig. 5 is a vertical longitudinal section of the boiler, similar to Fig. 3, but showing the several sections of the same separate for convenience in Iexplaining the invention.

Figs. 6 and 7 are vertical transverse sections, taken on the correspondingly numbered lines in Fig. 5.

In the following description similar characters of reference indicate like parts in the several iigures of the drawings.

In its general construction this boiler consists oi a base, a body resting on the base, and a cap or hood supported on the body.

The base which is mounted upon a foundation ICl of brick or any other suitable material is preferably constructed in the form of a box or enclosure which is equal in length and width to the size of the boiler and comprises two upright longitudinal side Walls ll, i 2 and two upright transverse walls I3, It connecting the corresponding front and rear ends of the side walls, these members being preferably constructed of sheet steel or rolled boiler plate and resting at their lower edges on the foundation, as shown in Figs. 1-7. present case, is divided by a transverse upright partition I5 of brick or other suitable material The space within this base, in the into a front pit i3 and arear pit I1 for the reception of ashes when heating the boiler with a hard fuel such as coal, wood or refuse, or these pits may contain parts of the burner mechanism Whenthe boiler is heated by gas, oil, or mechanical stoker.

In the present construction it is assumed that hard fuel is used as the heating medium and for this purpose a comparatively long grate I8 is arranged at the upper edge of the base in the front pit for supporting the fuel and for a like purpose a comparatively short grate I9 is arranged at the upper edge of the base in the rear pit, these grates being preferably mountedon brackets 2t projecting inwardly from the side Walls of the base.

Access to the front pit may be had through doors 2i in the front wall I3 and a door 22 in the adjacent part of one of its side walls and access to the rear pit may be had through a doo 23 in one of the side walls of the base.

The body of the boiler comprises a plurality of sections which are mounted on the base in a longitudinal row and in the preferred construction form a front combustion chamber 24 above the front grate I8 and a rear combustion chamber 25 above the rear grate I9. Although the number of sections in the body may vary to suit different sizes and conditions the organization shown in the drawings comprises four sections of which two form part of the front combustion chamber, one forms part of the rear combustion chamber, and one forms part of both of these chambers. The foremost of these sections is pro,- vided with two upright longitudinal water legs 26, which are arranged on transversely opposite sides of the front part of the front combustion chamber and rest at their lower ends on the adjacent side brackets 20 of the base, an upright front water leg 2l arranged transversely on the front side of the front combustion chamber and connected at its opposite vertical ends with the front ends of the respective side legs 26, a horizontal water chest 28 arranged transversely above the front combustion chamber and connected with the upper ends ofthe front and side legs 21, 26, and a plurality of upright heating tubes 29 arranged in the chest 28 and connected at their lower and upper ends with the upper and lower walls 30, 3| thereof so that the lower ends of these tubes open into the upper part of the front combustion chamber. The above mentioned bottom and top walls of the chest 28, the front and rear walls 32, 33 thereof, the inner and Outer Walls 34, 35 of the'side legs 26 and v:form an integral structure.

`che inner and outer Walls 36, 31 of the front leg V21 are made of rolled boiler plate or sheet steelV the adjacent edges of which are connected by welding, electric, acetylene or otherwise, so as to The upright walls of this chest are connected by stays or rods 38, and the respective upright walls of the side and front legs 26, 21 are'connected by stays or rods 39, 40, thereby holding these walls against displacement under the vpressure to which they are subjected while in use.

In rear of the front body section is arranged an intermediate body section which has generally the Yform of an inverted U and comprises twoupright longitudinal legs 4|, arranged on transversely opposite sidesof the front combustion chamber and resting at their lower ends on the adjacent side brackets 20 of the base and abutting at their front edges against the rear edges of the legs 26, a horizontal water chest 42 aro Vranged transversely over 'the front combustion chamber and bearing against the chest'29 and connecting. the upper ends of the side legs 4| anda plurality of upright heating tubes 43 arranged in the chest 42 and'connected at'their lower and upper ends with the lower and upper walls 44, 45 of this chest so that the lower ends Vof these tubes open into the upper part of Ythe front combustion chamber.

Said lower and upper Awalls of the chest 42, the front and rear walls 46, 41 and the innermand` outer walls 48, 49 are all made of rolled boiler .plate or sheets of steel which are integrally connected by electric or gas welding and the walls of this chest are connected by horizontal stays or rods 50, and the walls of the legs 4| are connected by stays or rods 5| to prevent spreading of these walls under pressure. f

In rear of the intermediate body section is a partition body section which forms partof the enclosure for the front and the rear combustion chambers. This partition body section comprises two upright longitudinal legs 52 arranged on transversely Vopposite sides of the frontand rear combustion chambers and resting at their lower ends onthe adjacent side brackets 20 of the base and fitting at their front ends against the rear ends ofv the legs 4 I, an upright partition leg 53 arranged transversely between the front and rear combustionY chambers andY resting at its lower end on the partition |5 between the frontY and rear pits, a horizontal water chest 54 extending transversely over the adjacent parts of the front and rear combustion chambers and bearing against the chest 42 and connecting the upper ends of the legs 52, 53, and a plurality of upright heating tubes 55, 56 arranged within the chest 54 and connected at their lower and upper ends with the bottom and top walls 51, 56 of this chest so that the lower `ends of the tubes 55 open into the front combustion chamber and the lower ends of the tubes 56 open into the rear combustion chamber. The front and rear transverse walls 59, 60 of the chest 54 are connected by longitudinal stays or rods 6|, its longitudinal side walls are connected by transverse stays 62 and the longitudinal walls of each of the legs 52 and the upright partition leg 53 are connected by stays or rods 63 to prevent these walls from yielding when subjected to internal pressure. The several walls of the' partition body section are constructed of' rolled boiler plate or sheets of steel which are Welded together .to form an integral structure.

The rearmost section of the body comprises two upright longitudinal water legs 64 whichare constructed like the longitudinal legs of the front, intermediate and partition sections of the body and engage legs of the partition section While their lower ends rest on the adjacent brackets 2O of the base on opposite sides of the rear combustion chamber, a rear upright Water leg 55 arranged transversely at the rear end of the rear combustion chamber and resting at rits lower end on the transverse rear bracketsV 2li of the base and connected at. its opposite vertical edges with the rear edges cf the side legs 64, a horizontal water chest E6 arranged over the rear part of the rear combustion chamber and engag-V stays or rods 12, its longitudinal side walls are connected by transverse' rods 13, the upright walls of each side leg 64 are connected by stays or rods 14 and the walls 15, 16 of therleg 55 are connected by stays or legs 11, thereby preventing these walls from spreading under pressure. The several walls of the rearmost body section are constructed of rolled boiler plate of sheets of steel which are connected by any well known method of welding in order to integrally connectV the same. The lower end of each upright leg of the several body sections is closed by a plate of sheet steel or rolled boiler plate and may either consist of an extension on one wall of the respective leg and welded to the companion wall as shown at 82 in Figs. 3 and 4, or the same may be made separate and welded to both walls of a water leg, as shown at SES in Fig. 3.

The cap or hood of the boiler is provided on its under side with a dome or passage 18 into which the upper ends of the heating tubes of the several body sections are arranged. This cap is preferably constructed in sections and in the present case consists of three sections arranged in a longitudinal row. The foremostl section is arranged over the whole of the front body section and part of the intermediate body section arranged next to the front body sectionand comprises two upright longitudinal water legs 19 arranged on transversely opposite sides orf the front part of the dome and resting on the front and intermediate body sections, an upright front water leg 8|) arranged transversely on the front part of the foremost body section and connecting with the front ends of the side legs. 19 of the respective cap section, and a horizontal water crown 8| connecting the upper edges of said side legs 1:1 and front leg 8B. Each of the side legs has inner and outer walls 84, 85 which are connected at their lower edges by a plate 86, the front leg 8B has inner and outer walls 81, 88 which are connected at their opposite edges with the corresponding.

with the upper and lower edgesof an end plate |02 by welding or otherwise.

To prevent the wallsf of this capsection from spreading under pressure the same are preferably connected by suitable strengthening or reinforcing means, such, for example, asthe stays; bolts or rods |03 connecting the` walls ofthe front cap water leg 80, and the stays, bolts or rods |04 connecting the inner and outer Walls ofthe water crown 8|.

The centralsection ofthe cap or'hood is engaged at its front end with the rear end of the front cap section and partly over the intermedi--y ate body section and partly over the partition body section and comprises twoupright longitudinal water legs |05 arranged on transversely opposite sides of the central part of the dome 18 and a horizontal water crown |06 connectingthe upper ends of the side legs |05'. Each of the capn legs |05 is provided with inner` and outer walls |07, |08 which are connected at their horizontal lower edges by horizontal end plates |09'. The crown of the central capy section has` inner andiouter walls ||0, which connect at their opposite longitudinal edges, respectively, with the corresponding upper edges of the inner andouter walls of the side legs |05. The corresponding front and rear edges of the walls of the water legs and the water crown of the central cap sec-` tion are connected, respectively, by end plates, 2, ||3, and these walls are braced relative to each other by stays, bolts or rods which connect them, as shown for example at I |4 in Figs. 3, 4', 5 and 6.

The rear section of the cap orl hood extends over the entire rearmost body section and over part yof the partition body section and engages its front end with the rear end of the central cap section, and comprises two upright longitudinal water legs ||5 which rest at their lower ends on the transversely opposite parts of the partition body and the rear body sections of theboiler, a rear upright water leg IIB mountedl transversely on the rear part of the rear body section and connected at its opposite vertical ends with the rear ends of the side legs I|5 and a horizontalwaterk crown I Il arranged overA the rear part of the dome and connecting the upper ends of the side water legs ||5 and the rear water leg H6; Each of the side water legs |I5 is provided with inner and outer walls ||8, ||9 which are connected at their lower edges by a horizontal end platev |20, the water leg IIS has inner and outer walls I2 I, |22 which are connected at their lowerA edges by a horizontal end plate |23, the crown has inner and outer walls |24, |25 which are connected with the upper edges of the walls of the side legs |I5 and the transverse leg IIS, and the front edges of the inner and outer' walls of the side legs I5 and the crown ||'I are connected by vertical end plates |26. The inner and outer walls of the transverse leg IIB are connected by stays, bolts or rods |21 for'sustaining the same' against internal pressure and inner and` outer walls of the side legs ||5 and the crown may likewise be reinforced against displacement by stays, bolts or rods, such as those shown at. |28

which connect the walls of the crown I I'I.

The walls and end plates of the several sections of the cap or hood are constructed of what is commonly known as rolled boiler plate or sheet steel and the parts of each of. these sectionsA areA united into one integral structure by welding them together in any well known manner eitherelectrically or by gas.

The lower parts of the water spaces in: the

severalfbody sections are placed in communication with each other so that the water can flow freely from one to the' other and distribute itself uniformly in the boiler. This is preferably accomplished by two manifolds or Amain conduits |23v arrangedalong the lowermost parts of the outer longitudinal sidesof the several body sections and connected with each of said sections by transverse branch pipes |30. Fresh water is supplied to the boiler in any suitable manner but preferably by connecting one or both of these manifolds with a source of water supply. A free circulation is also established between the several body sections and the cap sections, the preferred means for this purpose consisting of pairs of tubular necks or'short pipes |3|, |32 communicating respectively with the interior of the body sections and cap sections and projecting laterally from opposite -longitudinal sides thereof adjacent to the horizontal joint between the body and cap sections, andan elbow |33 connecting the outer ends of each pair of necks, as shown in Figs. 1, 2, 3, 6 and '7.

To permit of completely emptying the water from the boiler andv removing any mud which mayY have settled in the lowermost part of the water legs of the body sections drain openings |34 are provided at suitable places in the lowermost part of the outer Walls of these legs which openings are normally closedby screw plugs |35.

When burning hard fuel, such as coal, coke or wood the same is introduced into the front combustion chamber and placed upon the front grate I8 through a stoke hole or feed passage or opening |36. arranged in the lower Ypart of the transverse water leg of the foremost body section and normally closed by a door |31. The smoke and waste gases resulting from the combustion of the fuel escapes from the rear combustion chamber and conducted to -the chimney or flue through a smoke pipe or outlet |38 arranged n the lower part ofthe transverse water leg of the rearmost body section.

As the fuel burns in the front combustion chamber the hot flames and gases pass upwardly therefrom in contact with the inner walls of the respective body sections `and through the heatingl tubes or flues of the front and intermediate body sections and those of the partition body sections which are arranged in front of the water partition leg 53, thence upwardly into the front part yofl the dome of the sectional cap, thence rearwardly in this-dome to the rear part ofthe same and in contact with the adjacent walls of the several body and cap sections, thence downwardly through the heating tubes or ues in the rearmost body section and those tubes or iiues ofthe partition body sections which are arranged inv rear ofv the partition water leg, thence downwardly in the rearcombustion chamber in contact with the several'walls of the respective body chambers, and then escape through the smoke pipe or outlet passage |38 to the chimney. During this movement of the hot gases the same contact with maximum surface of the boiler and transmit heat to the water while the same is divided to very large extent into comparatively small rnasses so' that all parts of the same are eiectively reached by the heat, thereby enabling heating the water to be heated rapidly and economically.

Due to the use of rolled boiler plate as the walls of' the body and cap sections of the boiler which material is very thin compared with cast iron',.the heatof thehot gases is capable of pass- 4 ing more rapidly and effectively through these walls and thus heat the water quicker and also maintain the water at a higher temperature by the consumption of a given amount of fuel.

The hot water or. steam may be drawn v`off from the boiler inany desired manner, for instance by a manifold delivery pipeV |39 arranged horizontally Yover the cap or hood and connected` Inl addition to serving asa downtakeufor the hotgases vin the rear combustion chamber for obtaining the Vmaximum heating effect of the same on the water before they escape from the boiler,l this rear combustion chamber may be utilized as an incinerator for burning rubbish and .they like. on the rear grate in this chamber and thus not only readily disposing of this rubbish but also utilizing any heating Value contained therein. This rubbish may be introduced into the rearcombustion chamber and deposited on the rear grate I9 through a feed opening orpassage |46 formed`V on the Alower parts offadvjacent side legs ofthe rearmost and partition body sections of the boiler on one side of the same above the rear grate which rubbish feed passage is normally closed by a door |41.

In order to prevent the names and hot gases resultingfrom the burning of the rubbish on the rear grate from passing directly out through the smoke pipev |38, an upright baille or're thereby ,avoiding waste.

bridge |48 is preferably arranged transversely over the rear grate between the feed opening |46 and the smoke outlet |38 and projecting upwardly from the rear grate andpartly across the lower s ide of the smoke pipe so that the hot gas and smoke rising from the fuel on the rear grate are compelled to first strike the inner Walls of -tlie respective body sections before their escape wall of the base.

In this construction the surface exposed to the heating medium-is properly proportioned to the area of the grates and is ample for utilizing vto the fullest extent the -fuel which is consumed The number of sectionsemployed in the boiler may be varied to suit the required capacity of the same and also meet varying conditions of installation. lInasmuch as the area of the upper horizontal walls of the water chests of the several body sections is comparatively small a minimum of horizontal shelf area is present onrwhichsoot and flying ashes might lodge, thereby maintaining the heating surface in the most effective condition and also reducing'any tendency to retard the draft through the boiler.

Due to the form of the several sections of the boiler the same can be made in any size or number and comparatively small and thus render it lpossible* to pass the same individually through small door openings vor-vlike passages when this is necessary. Y c f No unusualy mechanical knowledge-is required to erectl this boiler as all the parts are of simple construction. the `severa-l sections arecon Ythe exterior of the boiler the same are ,visible at all times for inspection and care.' Y 1 Byproviding aA front combustion chamber b elow the rst set of heating tubes forming the first or Vuptake pass for the heating medium and a secondary grate inthe rearY combustion below the second set ofheating tubes forming the seoond or downtake pass, it is possible to not only employ a main fuel for heating the Water but also an auxiliary'fuel such as rubbish to supplement the heating effect on the water `and there-'f by enabling this boiler tobe utilized as an incinerator without added expense.

As the products vof combustion contact with the uppersurface of the dome in the cap sections a superheating effect is produced on the vaporsv or-the water'infthe crowns of the cap sections,

thus lutilizing the fuel mostadvantageously.

FreeV circulation of the; water is. possible through allparts ofV the boiler and no obstructions-exist which interfere with the directV up and downA travel of the waterin the several sections.' By constructing all of the sections of the boiler of rolled boiler plate the same are more 'flexible than conventional boilers made of cast iron and the same are also not subject to cracking and consequent leakage.

As afwhole this boiler isexceedingly simple in construction, its several parts can be manufactured and assembled at 10W cost and the same has no parts which areliable to get out of order thus reducing the cost of maintenance to a minimum.

I claim as my invention:

1. A boiler comprising a lower base, a body` section resting on the base, anda cap resting on `the body section, said body and cap sections being constructed as separate units which are independent and separable from one another, said base containing a pit, said body section having two vertical water legs on its opposite sidesforming a combustion space between them, and a transverse chest connecting the upper ends of said legs, said cap having a `Water space and containing a dome which opens .downwardly-and a plurality of vertical heating tubes arranged in said chest and openingrat their lower ends into said combustion space and at their upper ends into said dome.

2..A boiler comprising a base, body sections arranged lengthwise one behind the other on said base andl each having vertical water legs on its oppositev sides and forming a combustion space between the same, and a transverse chest connecting the upper ends of said legs, vertical heating tubes arranged in each of said chests and opening at their lower ends into the combustion space of the respective body section, and a cap having a water space and provided on its underside with a dome' communicating withthe upper ends of the tubes of the respective body sections, said body sections and cap being constructed as separate units which are independent and separable from one another.

3. A boiler comprising a base, body sections arranged lengthwise one behind the other on said base and each having vertical water legs on its -As all the connections between` opposite `sides and forming a combustion space between the same, and a transverse chest connecting the upper ends of said legs, vertical heating tubes arranged in each of said chests and opening at their lower ends into the combustion space of the respective body section, and a cap having a waterspace and extending over adjacent body sections and resting thereon and provided on its underside with a dome which communicates with the upper ends of the tubes of the respective body sections, said body sections and cap being constructed as separate units which are independent and separable from one another. 1

4. A boiler comprising a lower base, a body section resting on the base, and a cap having a water space and resting on the body section, said base containing a pit, said body section having two vertical water legs on its opposite sides forming a combustion space between them, a transverse chest connecting the upper ends of said legs, said cap containing a dome which opens downwardly, a plurality of vertical heating tubes arranged in said chest and opening at their lower ends into said combustion space and at their upper ends into said dome, and a conduit connecting the interior of the body section with the interior of the cap, said body sections and cap being constructed as separate units which are independent and separable from each other.

5. A boiler comprising a base, body sections arranged lengthwise one behind the other on said base and each having vertical water legs on its opposite sides and forming a combustion space between the same, a transverse chest connecting the upper ends of said legs, and vertical heating tubes arranged in each of said chests and opening at their lower ends into the combustion space of the respective body section, a cap having a water space and extending over adjacent body sections and resting thereon and provided on its underside with a dome which communicates with the upperends of the tubes of the respective body sections, and external conduits connecting the interior of each of said body sections with the interior of said cap, said body sections and cap being constructed as separate units which are 'independent and separable from each other.

6. A boiler comprising a base, body sections arranged lengthwise one behind the other on said base and each having vertical water legs on its opposite sides and forming a combustion space between the same, a transverse chest connecting the upper ends of said legs, an-d vertical heating tubes arranged in each of said chests and opening at their lower ends into the combustion space of the respective body section, a cap having a water space and provided on its underside .with a dome communicating with the upper ends of the tubes of the respective body sections, and a conduit connecting the interior of adjacent body sections, said body sections and cap being constructed as separate units which are independent and separable from each other.

7. A boiler comprising a base, a front body section, a rearward body section arranged in rear of the front section and a cap arranged above 'said body sections and having a water space, said front body section having an upright front water leg extending transversely across the front section, two side upright water legs arranged on transversely opposite sides of this section and connected at their front ends with the opposite vertical ends of said front leg, a horizontal chest connecting the upper ends of said' front and side legs and forming therewith a rearwardly opening front part of a combustion chamber and vertical heating tubes arranged in said chest and opening at their lower ends Vinto said front part of the combustion chamber, said rearward body section having an upright transverse partition leg, two side upright water legs arranged on transversely opposite sides of this section and connecting with the opposite vertical edges of said partition leg and a horizontal chest connecting the upper ends of said legs of said rearward body section, and a cap arranged above the front and rearward body sections and provided on its underside with a dome which communicates with the upper ends of said heating tubes, said body. sections and cap being constructed as separate units which are independent and separable from each other.

8. A boiler comprising a base, a front body section, a rearward body section arranged in rear of the front section and a cap arranged above said body sections and having a water space, said front body section having an upright front water leg extending transversely across the front section, two side upright water legs arranged on transversely opposite sides of this section and connected at their front ends with the opposite vertical ends of said front leg, a horizontal chest connecting the upper ends of said front and side legs and forming therewith a rearwardly opening front part of a combustion chamber and vertical heating tubes arranged in said chest and opening at their lower ends into said front part of the .combustion chamber, said rearward body section having an upright transversepartition leg, two side upright water legs arranged on transversely opposite sides of this section and connecting with the opposite vertical edges of said partition leg and a horizontal chest connecting the upper ends of said legs of said rearward body section and forming therewith a forwardly opening rear part of said combustion chamber, and a cap arranged above the front and rearward body sections and provided on its underside with a vdome which .communicates with the lupper ends of ysaid heating tubes, saidl body secvtions and .cap being .constructed as separate units which are independentand .separable from veach iront section, two side upright water legs arranged on transversely opposite sides of this'section and connected at their front ends with the .opposite vertical ends of said front leg, a horizontal chest connecting the upper ends of said 'front and side legs and forming therewith a rearwardly opening front part of a combustion chamchest and openingat their lower ends into said .front part of the combustion chamber, said rearward body section having an upright transverse partition leg, two side upright water legs arranged .on transversely opposite sides'of this section `and said partition leg and a horizontal chest connecting the upper ends of said legs of said rearward `body section and forming therewith a forwardly opening rear part of said combustion chamber,

`heating tubes arranged in the chest of said rearward body sectionV and opening into the partof the combustion chamber therein, and a caparyranged-.above the yfront and rearward body secber and verticalheating tubes -arranged in said Aconnecting, lwith the vopposite vertical edgesof ,tionsl and provided on its underside with a dome which communicates with the upper ends of said heating tubes, said body sections and cap,being constructed as separate units which arefi independent and separable from each other. v

1G. A boiler comprising a base, a front body section, a rearward body section arranged in rear of the front section and a cap arranged above `f said body sections and having a water space, said front'body section having an upright front water Y leg extending transverselyv across the front section, two side uprightV water legs arranged on transversely opposite sides'fof this section and connected at their frontr ends with the opposite vertical ends of said front leg, a horizontal chest connecting the upper ends of said front and side legs and forming therewith a rearwardly opening fro-nt part of a combustion chamber and vertical 'heating tubes arranged in saidchest and opening at their lower ends-into said irontpart oi' the combustion chamber, said rearward body section havingan upright transverse vpartition leg,

two side upright water legs arranged on transversely opposite sides of-this section and connecting with the opposite vertical edges of said'partition leg and a horizontal chest connecting the -upper ends of said legs of said rearward body sections and cap being constructed as separate units which are independent and separable from each other. l

11. A boiler comprising a base, Va front body section, a rearward body sectionarranged in rear of the front section and a cap arranged above said body sections and having a water space, said front body section having an upright iro-nt water leg extending transversely across: the front section, two side upright water legs arranged on transversely opposite sides of this-section and connected at their front ends with the opposite vertical ends of said frontleg,.a horizontal chest connecting: the upper ends of said front and side 'legs and forming therewith arearwardly opening front part of aicombustion chamber and vertical heating tubes arranged in said chest and opening atV theirlower ends into said front Ypart of the combustion chamber, said rearward body section having an upright transverse partition Y leg, two side upright water legs arranged on transversely opposite sides of this section andv connecting with .the opposite Vvertical edges of said partition leg Vand a horizontal chest connecting the upper ends of said legs of said rearward ,body section, anintermediate body section arranged betweensaidrfront body section and rearward body section and havingtwo` upright Y sidewater legs, ahorizontal chest connecting the jupper ends of vthe'respective side legs and formingtherewith an Yintermediate partfof said combustion chamber, heating tubesarranged Vin the chest of said intermediate body section andropening at rtheir lower ends into theV part'of the combustion chamber in the respective body section, and a cap arranged above the front and rearward body sections and provided on its underside with a dome which communicateswith the upper ends of said heating tubes, said body sec? tions and cap being constructed as separate units which are independent and separable from each other.

l2. A boiler having a front body section, a rear` body section, an intermediate body section, and a cap arranged above said body sectionsand having a water space,each of said body sections having two upright water legson transversely oppositesides thereof, an upright transverse wall connecting said legs and ahorizontal chest connecting the upper ends of said legs and wall, Ythe 'K legs, walls and chests of said front and'intermediate bodysections forming between them a front combustion chamber and theA legs, walls and chests of said intermediate and rear body sections forming between them va rear combustion i chamber, upright heating tubes arranged in each of said chests and opening at their lower endsV a cap arranged above said body sections and having a water space, each of said body sections having two upright water legs on transversely opposite sides thereof, an upright transverse wall connecting said legs and a horizontal chest conlegs, walls and chests of said front and intermediate body sections forming between them a front combustion chamber and the legs, walls and necting the upper ends of said legs and wall, the

chests of said intermediate and rear Vbody sec- .i tions forming between thema rear combustion chamber, upright heating tubes arranged in each of said chests and vopeningat their lower ends into the respective combustion chamber, and said cap being provided on itsunderside' witha dome which communicates with they upper ends Vof the several-heatingtubes, said body sections and cap being constructed as separateunits which are independent and separable from each other, the transverse wall of said front body section being provided wtih an inlet to the vfront combustion chamber, and the transverse wall of said rear body section being provided with an outlet for the products of combustion.

14. A boiler having a front body section, a

rear body section, an intermediate body section, n

and a cap arranged above said body sections and having a water space, each of said body sections having two upright water legs on Y transversely opposite sides thereof, an upright transverse wall connecting said legs and a horizontal chest connecting the upper ends of said legs and wall, the

legs, walls and chests of said front and intermediate body sections forming between them a front combustion chamber and the legs, walls Y and chests of said intermediate and rear body sections formingbetween them a rear combustion chamber, upright heating tubes arrangedin each of said chests and opening at their lower ends into the respective combustion chamber,

and said cap being provided on its undersidek front combustion chamber. the transverse wall" of said rear body section being provided with an outlet for the products of combustion, and a water leg forming part of said rear combustion chamber and provided with an inlet for combustible material.

15. A boiler having a front body section, a rear body section, an intermediate body section, and a cap arranged above said body sections and having a water space, each of said body sections having two upright water legs on transversely opposite sides thereof, an upright transverse wall connecting said legs and a horizontal chest connecting theupper ends of said legs and wall, the legs, walls and chests of said front and intermediate body sections forming between them a front combustion chamber and the legs, walls and chests of said intermediate and rear body sections forming between them a rear combustion chamber, upright heating tubes arranged in each of said chests and, opening at their lower ends into the respective combustion chamber, and said cap being provided on its underside with a dome which communicates with the upper ends of the several heating tubes, said body sections and cap being constructed as separate units which are independent and separable from each other, the transverse wall of said front body section being provided with an inlet to the front combustion chamber, the transverse wall of said rear body section being provided with an outlet for the products of combustion, a water leg forming part of said rear combustion chamber and provided with an inlet for combustible material, and a grate arranged in the lower part of said rear combustion chamber.

16. A boiler having a front body section, a. rear body section, an intermediate bodysection, and a cap arranged above said body sections and having a water space, each of said body sections having two upright water legs on transversely opposite sides thereof, an upright transverse wall connecting said legs and a horizontal chest connecting the upper ends of said legs and wall, the legs, walls and chests of said front and intermediate body sections forming between them a front combustion chamber and the legs, walls and chests of said intermediate and rear body sections forming between them a rear combustion chamber, upright heating tubes arranged in each of said chests and opening at their lower ends into the respective combustion chamber, and said cap being provided on its underside with a dome which communicates with the upper ends of the several heating tubes, said body sections and cap being constructed as separate units which are independent and separable from each other, the transverse wall of said front body section being provided with an inlet to the front combustion chamber, the transverse wall of said rearbody section being provided with an outlet for the products of combustion, a water leg forming part of said rear combustion chamber and provided with an inlet for combustible material, a grate arranged in the'lower part of said rear combustion chamber, and a fire wall in said rear combustion chamber above the rear part of said grate and between said inlet and outlet of said last mentioned chamber.

JOHN BERENT. 

